66135663925 has 6 divisors (see below), whose sum is σ = 82008223298. Its totient is φ = 52908531120.

The previous prime is 66135663917. The next prime is 66135663929. The reversal of 66135663925 is 52936653166.

It can be written as a sum of positive squares in 3 ways, for example, as 10789807876 + 55345856049 = 103874^2 + 235257^2 .

It is not a de Polignac number, because 66135663925 - 2³ = 66135663917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66135663929) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1322713254 + ... + 1322713303.

Almost surely, 2^66135663925 is an apocalyptic number.

It is an amenable number.

66135663925 is a deficient number, since it is larger than the sum of its proper divisors (15872559373).

66135663925 is a wasteful number, since it uses less digits than its factorization.

66135663925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2645426567 (or 2645426562 counting only the distinct ones).

The product of its digits is 5248800, while the sum is 52.

The spelling of 66135663925 in words is "sixty-six billion, one hundred thirty-five million, six hundred sixty-three thousand, nine hundred twenty-five".